A Stencil Complier for the Connection Machine Models CM-2/200

Abstract

In this paper we present a Stencil Compiler for the Connection Machine Models CM-2 and CM-200. A stencil is a weighted sum of circularly-shifted CM Fortran arrays. The stencil compiler optimizes the data motion between processing nodes, minimizes the data motion within a node, and minimizes the data motion between registers and local memory in a node. The compiler makes novel use of the communication system and has highly optimized register use. The compiler natively supports two{dimensional stencils, but stencils in three or four dimensions are automatically decomposed. Portions of the system are integrated as part of the CM Fortran programming system, and also as part of the system microcode. The compiler is available as part of the Connection Machine Scientific Software Library (CMSSL) Release 3.1.